Black-out lamp



June 27, 1944- W. TRAUTNER 2,352,459

I BLACKOUT LAMP l Filed Marchv 5o,A 1942 INVENTOR. 446W @A01-Nag.

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Patented June 27, 1944 UNITED .STATES 2,352,459 AlilLfliUK-OU'I LAMP Wagn Trautner, Hamilton, Ohio, assignor'to The' K-D Lamp Co., tion cf Ohio Cincinnati, Oh-ioya oorpora- Application March 30, isilseiiai No. 436,875.5 y

e claims. (c1. 24o-:75V

My invention relates to lamps which emit a carefully restricted beam visible only from a narrow Zone and not for any great distance, more particularly designed for boa-ts and which emit distinctive colored rays to indicate port or starboard, ordinarily the standard green and red. Y

In my application for Letters Patent Serial No.

435,365 filed Mar. 19, 1942, I have described a,

lamp having a zone of visibility which is restricted in degrees, but which embodies within it the fundamentals of my present lamp. As in the .said application my present lamp includes ay light source, shrouded above and below and ex-v posed only through restrictedslits in a mask and in which there are additional shrouds. which are loca-ted far enough away from slits of the mask to confine the light rays emitted from the lamp to these which pass througha refraction-lens located in the Zone of the said additionalshrouds. In the present invention itis my objective to adapt the principles of the lamp of my said ap plication to a 360 degree Visibility lamp, to provide for two color Zones in 'connection-with they mask, and to assuring that iii-assembly of the lamp and mounting thereof, there is positivein` dication to require that the two colors are orient--y ed properly, and that the lamp will be mounted properly with relation to the boat orother moving device which is. served by the lamp. In the illustrated exemplicationthelamp -is intended to be substituted for a searchlightin a boat, to be located at a point visible within a full 360 degrees. By suitable arrangements the lamp can be quickly oriented exactly in position onf the boat in the dark and the casing is accurately arranged with reference to the interior of thelamp, so that the result of mounting the lamp will be to secure a definite orientation ofthe two colors with reference to the boat. There are inaddition structural details incident to making the new lamp one which is visible at 360 degrees, and to provide strength, accessibility, water tightness, and ability to withstand rough' treatment. In the drawing: y y f Figure 1 is a top plan view of the lamp. Fig. 2 is a side elevation thereof.

Fig. 3 is a bottom plan View thereof. Fig. 4 is a central vertical section thereof. Fig. 5 is a sectionon the line 5-5 of Fig. 4.y l Fig. 6 is a perspective of the lamp base.v

f Fig. 7 is a perspective of the glass top lens unit.

lamp.

Referring to the specific embodiment illustratand.

Fig. 8 is one of the color sectors used in the` l ed which will .serve as an example of my'invention,.the novelty ofwhich Will be set forth in the claims, the base consists of a casting I of circuslar: shape Vand cupform, having a threaded boss 2 lcentrally thereof, into which is threaded the mounting post 3, there. being a lock nut 4 for the proper position of the post. This post may have a special shape to operate with a special socket on the boat to assure precise orientation of the base of the lamp when mounted. As showny a ilat 4a is formedon the post for engagement with a set screw in the socket (neither of which are shown). Mounted within the base is a dome shaped socket mount 5, which is held in place in some convenient manner such as by removable set screws 5c in the side ofthe base casting. The casting has a prominent externalrib 6 formed thereon, which can be easily distinguished by the 'fingers and which serves in mounting the lamp in placev in total darkness. The casingalso has welded to the top annulus thereof, a shee metal holder 'I for the glass Aof the lamp.

vThis holder has an inturned ange 1a, which is formed with notches 1b andv 'lc therein. In the form shown the notch 'lc is diierentfrom the other; notches being wider, a device which assures proper orientation of the glass member of the lamp. g

'The glass is a dome shaped molded piece 8, preferably of .heavy glass with an intermediate band V8a thereon molded to forma refraction lens to conne light rays impinging upon it within a desired angle of deflection. The lower annulus 9 of this glass 3 will enter the sheet metal holder, and there are ribs 9a and 9b on this annulus which project laterally therefrom. These ribs must pass through the notches lb and 'lc .in the holder flange before the glass can be vseated on the holder. The rib 9b is longer than the ribs 9a. and can only enter the longer notch lc, wherefore proper orientation of the glass is arranged, as has heretofore been noted. Some of the notches have a lip Td projecting downwardly at their ends which lips serve` asstops when the glass is inserted into Dlace and twisted to lock it down. There isa ange I0 formed yon the glass which is provided with a rubber gasket Il, and seats on the top of thel holder 1. l f

. Cast on the top of the flange l0 is a guide mark I2, which as will be noted, guides the as sembly of the lamp since in the final assembled form thisguide mark .will line up with the rib 6 on the base casting This guide mark I2 will also makeit easyto, lind the proper orientation of the glass for inserting it into the holder on the base, since it can be felt with the fingers in the dark.

The top of the glass, and down the sides thereof to the upper boundary of the refraction rib is coated with black light absorbent material as at I3. Press fitted into the glass from the bottom is a shroud ,and mask structure, the lower portion of which 'is channel shaped as at I4 to take a forced t over the bottom annulus of the glass, with an upstanding ring portion I and an open top I6 which will come down over the top of the dome 5 which contains the lamp socket 5a and the lamp 5b. Secured to this lower portion as by rivets is a member having a plate portion I1 complementary to the top I6 of the mounting member, an outer upstanding ring I8 which is coated with black light absorbent pigment, and a cylindrical mask portion I9, also so coated, said mask portion having a series of light slits I9a therein, through which rays from the lamp can emanate. The plate portion I6 has its central orice suiciently smaller than the orifice within the cylindrical mask that there can be inserted within this cylinder, resting on the top I6, two translucent color sectors 20.

A convenient way of inserting the sectors and holding them in place is to turn up a flange as at IIa about the orice in the portion I6. 'Ihen apply the mask and shroud piece I'I, I8, I9, and nally rivet the parts tightly together. This will hold the translucent sectors in place, and then in forcing the whole inner structure into place, the dividing line between the two color plates can be arranged with reference to the guide mark I2 on the glass.

The iinal result is that when the glass is mounted on the base the color sectors will find their dividing line exactly in line with the guide rib 6 and the guide mark I2. If the lamp then be mounted with the guide rib directly astern, the lamp will be correctly oriented.

Removal of the glass requires simply reversing the bayonet type interlocking structure, and withdrawing it. The dome on which the lamp socket is mounted can be released and removed by backing out the set screws 5a. Thus the lamp is readily accessible.

Since the lamp is intended as a black-out lamp visible only for a short distance, it can be used without revealing the presence of a boat to a distant enemy either on the sea" or-in the air. However, since both-colors areused, it canbe told what direction the boat lis moving, and whether it is backing or coming forward.

The lens and mask are arranged, preferably,

so that a narrow ribbon of light which at close range is a series of dots, or at longer range a band, is visible. and not only can the observer tell whether the boat is going at right angles to the observer or at wide angles which -Will miss the observer but if the band is divided being part red and part green, the observer can tell quite closely the angle being taken by the boat. This is because the beam can have anyl proportion of the two colors depending upon how closely it is aimeddirectly at the observer.

Since the lamp emits rays in 350 degrees, it is quite desirable that this last be true. Ordinarily navigation lights are so ,arranged that if a boat is approaching, the angle of approach cannot be told when both red and green are visible, there being usually ten degrees each way when both lights are visible and` no intermediate @position where one of the colors is partially visible and the other wholly visible. The color sectors are calculated as to amount of light emitted so as not to be visible at any great distance. The visible light due to the lens is a narrow band oriented horizontally so that there is an avoidance of the beam of one color mixing with a beam of the other color at a distance, thus even obscuring the weaker color. It may be advisable to make the green sector of a greater translucency than the red sector in order to avoid an undue over-balance on the red side at a distance.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:

1. In a blackout lamp having visibility at 360 degrees, a base, a glass having a bayonet type of interlock with said base, means for supporting a light source upon said base and within the glass, and a mask structure within the glass and supported thereby, and arranged to block all rays except interspaced spots of light, the glass having an annular refraction lens therein, and shrouds located to block rays from the light spots except those which pass through the lens.

2. In a blackout lamp having visibility at 360 degrees, a base, a glass having a bayonet type of interlock with said base, means for supporting a light source upon said base and within the glass, and a mask structure within the glass arranged to block all rays except interspaced spots of light, the glass having an annular refraction lens therein, and shrouds located to block rays from the light spots except those which pass through the lens, the said light source having translucent colored sectors between it and the mask.

3. In a blackout lamp having visibility at 360 degrees, a base, a glass having a bayonet type of interlock with said base, means for supporting a light source upon said base and within the glass, and a, mask structure within the glass arranged to block all rays except interspaced spots olf light, the lglass having an annular refraction lens therein, and shrouds located to block rays from the light spots except those which pass through the lens, the glass being dome shaped and the mask and shroud construction being a unitary structure having an inner cylinder as the mask and a shorter outer cylinder as the shroud, and means for supporting said structure within the glass, said glass having a shroud formed to block the top thereof and annularly of the glass beneath the top, thus setting up a 360 degree light slit.

4. In a blackout lamp having visibility at 360 degrees, a base, a glass having a -bayonet type of interlock with said base, means for supporting a light source upon said base and within the glass, and a mask structure within the glass arranged to block all rays except interspaced spots of light, the glass having an annular refraction lens therein, and shrouds located to block rays from the light spots except those which pass through the lens, the glass being dome shaped and the mask and shroud construction being a unitary structure having an inner cylinder as the mask and a shorter outer cylinder as the shroud, and means for supportingsaid structure within the glass, said glass having -a shroud formed to block the top thereof and annularly of the glass beneath the top, thus setting up a 360 degree light slit, said refraction lens being -located at the said 360 degree slit.

5. In a blackout lamp having visi-bility at 360 degrees, a base, a glass having a bayonet type of interlock with said base, means for supporting a light source upon said .base and Within the glass, and a mask structure within the glass arranged to block all rays except interspaced spots of light, the glass having an annular refraction lens therein, and shrouds located to block rays from the light spots except those which pass through the lens, the glass being dome shaped and the mask and shroud construction being a unitary structure having an inner cylinder as the mask and a shorter outer cylinder as the shroud, and means for supporting said structure within the glass, said glass having a shroud formed to block the top thereof and annularly of the glass be- 4neath the top, thus setting up a 360 degree light slit, the light supporting means within the base being in the form of a dome, demountably secured Within the base so as to bring the light source to the focal point of the refraction lens.

6. In a blackout lamp having visibility at 360 degrees, a base, a 'glass having a bayonet type of interlock with said base, means for supporting a light source upon said base and Within the glass, and a mask structure within the glass arranged to block all rays except interspaced spots of 1ightmeans in connection with the mask structure providing colored sectors, the glass having an annular refraction lens therein, and shrouds located to Ablock rays from the light spots except those which pass through the lens, the glass being dome shaped and the mask and shroud constructionv being a unitary structure having an inner cylinder as the lmask and a shorter outer cylinder as the shroud, and means for supporting said structure Within the glass, said glass having a shroud formed to block the top thereof and annularly of the glass beneath the top, thus setting up a 360 degree light slit, and means for mounting the mask structure Within the glass by a force fit, whereby the orientation of the colored sectors may be provided after insertion within the mask, said glass having indicia formed thereon, whereby the said orientation may be made, and the bayonet type mounting being adapted to receive the glass on the base in but one orientation.

VVAGN TRAUTNER. 

